Hampshire teenager Nathan Hartley who had a lifesaving bone marrow transplant to treat a rare genetic condition is to become a donor for his younger brother.

The four Hartley brothers, from Romsey, were all diagnosed with the life-threatening X-linked lymphoproliferative syndrome, or Duncan's Disease, in November 2003.

Joshua, 14, Nathan, 13, and 10-year-old Daniel have already undergone successful bone marrow transplants as this is the only cure for the condition.

Six-year-old Luke is due to have his transplant in March at London's Great Ormond Street Hospital and doctors have confirmed his brother Nathan is a perfect match as a donor.

The boys' dad David Hartley said: "Nathan is delighted that he will have the chance to save the life of his brother."